update coveralls badge url
update coveralls badge url

openaid-IATI/OIPA,zimmerman-zimmerman/OIPA,openaid-IATI/OIPA,openaid-IATI/OIPA,zimmerman-zimmerman/OIPA,openaid-IATI/OIPA,openaid-IATI/OIPA,zimmerman-zimmerman/OIPA,zimmerman-zimmerman/OIPA,zimmerman-zimmerman/OIPA